In recent years, so-called “bird strike” has become a problem, in which a moving object, e.g., a bird, intrudes into a region where an airport, a wind power generation facility, or the like is constructed, and collides with an aircraft taking off from or landing at the airport, or with a windmill of the wind power generation facility.
Accordingly, there has been desired a detection device for detecting the intrusion of a bird into such region.
As a device for detecting a bird, there is known a device for imaging a flying object at minute time intervals, analyzing a flight pattern of the flying object from a brightness pattern distribution, making a database of the flight patterns, and detecting whether or not the flying object is a bird (Patent Document 1).
Moreover, there is also known a device for calculating 3D coordinates of a flying object based on a distance between the flying object and a camera and azimuth data, and detecting a bird from a flight trajectory (Patent Document 2).
Further, there is known a device for imaging a flying object and a fixed object in the same image, thereby acquiring the height of the flying object (Patent Document 3).
Still further, there is known a device for determining whether or not a flying object is a bird based on the speed of the flying object (Patent Document 4).